Presence of the Enemy
by Sukio-chan
Summary: Grimmjow knew war shifted allies and borderlines. Rangiku found herself learning that enemies aren't always where they were last left.
1. Chapter 1

A/N: M Warning. Chapters containing Mature material will be marked at the beginning. Rating will go up in later chapters.

~ This is assuming Gin has been killed by Aizen, which I stoutly hope is not the case. ~

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The sounds echoing through the vacant halls of Las Noches were few, mostly of the back-up squads to Twelfth Division finding ways to amuse themselves or at least pass the time in the hulking complex Sousuke Aizen and his forces had occupied a year earlier.

Twelfth Division was on business – Kurotsuchi's business – and their captain took the matter seriously. So did everyone else; they didn't dare not. But with Captain Kurotsuchi's division intent on exploring every nook and cranny in search of any hidden Szayel Apporo research, none of them were taking the matters of other security into mind.

Rangiku Matsumoto sighed as she wandered the hall outside the center-most maze of corridors, hating that Divisions Ten and Nine had escorted Twelfth for the venture. She hated the sweltering heat of Hueco Mundo's day and the chill stillness of its night. She hated that there was no environmental controls functioning, making the outside temperatures creep into the gray-walled complex, and that she knew Kurotsuchi would take his painstaking time in his research.

It meant she and the other shinigami troops had nothing to do but loiter.

And most of all she hated that it was the very place Gin Ichimaru had spent so much time before his death. She resented it, the tall walls and Aizen and his minions and the limbo that her heart had been in for those months before she'd known whether he was indeed traitor, or indeed the man she thought she knew.

A few moments with him before he'd slipped into a new afterlife without her – that was all she'd gotten of him, all she had of him, the few fragments that she kept sweeping together to make into a bittersweet memory of knowing he was still hers, at the end.

She glanced to where Izuru Kira and Shuuhei Hisagi were approaching from another section of hallways. She pushed a bit of a smile onto her face, a forced movement over the last year.

"How much longer?" she asked when they caught up to her.

Izuru looked especially miserable. "Too long. We're back, if you want to go on your break."

Shuuhei nodded. "We've cleared the west sectors. Nothing there."

"There's nothing anywhere," she said, breathing a sigh in the void stillness of the halls. She put one hand to Haineko's hilt. "I can't wait for this to be over."

Both men nodded, Shuuhei throwing her as much of a sympathetic look as she'd let him. "Take a break. It isn't easy being here."

Rangiku wanted to laugh, but only managed more of a smile. "I don't see why Captain Kurotsuchi needs so much back-up. Nothing has happened in three days."

Shuuhei glanced down a dimly lit hall. "This waiting on nothing is killing me."

"Okay, I'll take a breather," she decided, letting another avenue of thought make the decision. She put a hand to her chest where the inoculants patch was barely hidden beneath an edge of her uniform top. "This thing is starting to itch. I don't think we need them anyway."

Shuuhei tried not to notice her fingers edging the white of her under robe. "They're about at their limits. Captain Kurotsuchi should call us all in soon."

"Maybe you could call a captains' meeting," she suggested, raising an eyebrow. "Or you," she added to Izuru. "You're both acting captains now."

There was no humor in Izuru's face. "I don't think that's going to be enough to convince Captain Kurotsuchi."

Shuuhei nodded, grinning a little. "Doubt it."

Rangiku turned. "I'll catch up with you soon."

"You want company?" Shuuhei called as she moved away. "I mean, no one's seen anything, but that doesn't mean there's nothing here."

She tossed him a smile over her shoulder. "Whatever Szayel Aporro did to kill off anything above a lowest class Arrancar worked. There's nothing, not even a drop of reiatsu left in this place."

He nodded, reading more than she allowed showing in her quick smile. "Watch your back, Rangiku."

She left them and headed deeper into the complex. She'd wanted to do it earlier, follow some faint trail that she alone could detect, something that called to her bones as only Gin could. It wasn't there, and she blamed the inoculants patch adhered to her chest.

On impulse she thought back to her captain's explanation.

"It's just a safeguard against any residual reiatsu-leaching walls Aporro may have set up," Captain Hitsugaya had told her when he'd given her the small, pale blue patch to put under her uniform in Tenth Division's headquarters three days ago. "It'll block anything from absorbing your spiritual pressure; no one wants their reiryoku monitored and blueprinted. Aporro has been known to do it."

Of course, Rangiku had proceeded to put the patch on in the office, and her captain had promptly blushed and yelled at her to _"Wait! Not here!"_

She smiled now at the thought. There was nothing like a brief flash of skin to change his dour mood into terror.

Her smile dimmed as she turned the next set of corridors where the halls began a slow descent to a lower level. She knew the dangers of treading anywhere Szayel Aporro had played. She knew what he'd done to Renji Abarai in mapping his reiatsu strengths.

Fatigue from the last three days caught up with her as she cautiously turned another corner of hall junctures. It was day three of a three-day stay at the vast complex while Twelfth conducted research. Short trips of a few days were what General Yamamoto wanted, and that's what the inoculants patches were designed for, but it made for tiring non-work. Sleeping on the floor or propped against a wall – even with Shuuhei offering a cozy shoulder when she drooped over to him – was getting old and she wanted her soft bed and an enormous meal. And a long bath.

Everything looked the same down the next corridor, as Rangiku expected. She sighed and slowed her steps, knowing the futilely of her venture into Las Noches' interior. One drawback of the patch under her robe was that it also dulled some of her own powers of perception. Twice Captain Hitsugaya had startled her while she made her rounds, and once had been when she was with the third seat from her own division, surprising both of them. A side-effect, he'd told her. An accepted trade-off.

She'd come to hate the term trade-off. A few in Soul Society had told her that was what Gin had done. Sacrificed himself. Taken a hero's course of action.

It hadn't helped her feel any better, even when the collective captains – hardly the Gotei 13 without thirteen captains – had given him a Soul Reaper's final ceremony.

Gin was still dead.

The white robes and burnt candles didn't change that for her.

"Damn you, Aizen," she murmured, pausing in the hall, hand clenched around her sword handle.

She didn't close her eyes as she wanted to, didn't try to imagine Gin standing before her, giving her that crooked smile and easy chuckle from her decades of memories with him. Instead she pushed one side of her robe a few inches to expose the small blue patch on her breast. She slowly peeled it off, chiding herself as she did.

If there was anything left of Gin Ichimaru, even a trace of his reiatsu, she wanted to feel it on her skin, and she couldn't do it with that blocker limiting her senses. She bit her lower lip as the patch came off, realizing she was holding her breath.

She waited, every nerve in her body waiting, reaching for any tendril of reiatsu ribbon that wanted to call out to her. Her fingers softened on the sword hilt, barely touching as she strained to feel something.

Anything.

All she felt was the thin particles that were always present at Hueco Mundo. No lingering trace of Shinso, no hint that Gin had ever been there.

Rangiku licked her lips, hoping, tasting nothing but three days worth of weary and a year of sorrow. She let herself lean against the wall behind her, the semi-lit hall seeming the perfect place to sense anything of Gin, as if he'd have left a grin smirking in the darkened corners.

Her eyes dropped down to the blue patch in her fingers. It was about spent, and she knew she should put it back on and weave her way through the halls to the rest of the divisions readying to leave for Soul Society.

Maybe there was something left of him, maybe she was just too tired to feel it. She looked up quickly as a heavier feeling ebbed through the hall.

It was nothing she recognized. She quickly stood straighter, pulling herself out of her pity, and then she heard a low hum of a generator from the way she'd come.

She sighed. So Captain Kurotsuchi has found another toy to investigate. He'd be delighted. It would also mean another trip back to Hell for the unlucky squads for back-up.

She carefully placed the patch back on her skin, smoothing it on her right breast, sighing at her frivolous and fruitless pursuit of a memory.

Her steps were slower as she turned back down the hall to find the rest of the divisions that were also ready to leave. She began the network of halls back to where she knew Shuuhei and Izuru would be.

From a secondary hall the last Espada watched her go, remaining hidden in the darker, unlit depths of the corridor, content to watch the misplaced shinigami.

Grimmjow Jaegerjaquez knew who she was. He knew who they all were, but he found her more interesting to watch. She'd been oblivious to him, which was just fine with him.

He knew who she was. She was the one who'd killed Nakeem Grindina.

Damn Aizen.

Grimmjow couldn't agree more.

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**A/N:** _Thank you for reading!_


	2. Chapter 2

That hum bought Rangiku and the other members of her Division and those of Ninth and Third another trip to Las Noches. With renewed vigor, Kurotsuchi began his meticulous research into a previously unknown corridor beneath the complex, delighting in the long rooms of experiments that either bored or frightened nearly everyone else.

With this new discovery came another blue patch for everyone, including Rangiku.

She donned it and waited out the three day leave to Las Noches with her fellow shinigami, boredom growing unendurable and nerves thinning when the three days turned into four, and then five.

By day five everyone had learned to amuse themselves or failing that, at least stay out of everyone else's way, especially Captain Kurotsuchi's way.

Rangiku departed Kira's company and moved down the darkened corridors of Las Noches to find nothing. The days had made her little captain cranky, with his citing Gotei protocol by the page and libre to Kurotsuchi, no avail. It gained no one anything, except headaches.

She followed the winding hall to nowhere, unimpressed by Aizen's one-time hollow greatness of towering walls and endlessly twisting corridors. The blue patch on her chest was a new one; Kurotsuchi had come prepared this time for any extensions, and everyone in each division had been given a fresh guard that morning.

Sadly, Kurotsuchi's preparations hadn't done the same for provisions, and they'd all been stuck with wafers of tasteless emergency rations for two days. Rangiku wasn't sure if she missed her bathtub or real food more.

She turned the next juncture of halls, pushing thoughts of Gin to the safety of her favorite corner in her mind. The hall opened out to an anteroom of sorts, to one side a wide granite stairway that led to a platform with an empty chair.

Throne, more likely, she thought, glancing to it for a moment.

It was empty, the large room vacant of any dead and undead alike, the imposing throne looking down on no one but her. Like a stage, she thought, awaiting its favorite actor to play god. It was a desolation she thought that would have been made no better with Aizen in it. She figured Gin had hated it. Probably most of the Arrancar and Espada, too, she deemed.

Except for that prissy Szayel, who seemed to enjoy the limelight, according to her conversations with Renji.

"Well, well," a male voice said from behind her, making her pivot, her hand dropping to her sword.

Grimmjow stepped from the shadows as her eyes found him in the dimness, grinning lethally at her startle. He shook his head, eyeing the open black collar above her sash. "A lost shinigami, are you?"

Rangiku stepped back, her senses sharpening as the tall Espada shortened the distance between them, forcing her nearly to the bottom of the grand steps. "You, you're all dead. All the Espada are dead," she stammered, backing up, trying to keep the distance between them.

He chuckled, eyes traveling from her shirt to her hair, pausing at various spots along the way. "Obviously not." He nodded at her rank attached at her waist. "Vice Captain Matsumoto."

She nodded slightly, swallowing down the assorted fears surfacing, damning the patch that had clouded his presence from her. She knew who he was, his rank, and the stories surrounding his cunning and strength. She also knew he wasn't one she wanted to face alone. She drew her sword, the metal sounding especially loud in the tall room.

His laugh gained a cruel sharpness. "You really think you have a chance in hell against me?"

"This is hell, so I suppose yes," she said, keeping her voice as level as she could despite her rising alarm.

He drew his sword, the metal quieter than her frantic pull. His leering grin changed, amusement hinting it. "You can sheath that and walk away," he said, backing her up the first step, sword still lowered. "Walk away, shinigami."

Rangiku knew there were no avenues of escape except past him, and knew he knew it as well. She let her blade drop, just enough to attempt passage. She circled to her left, his right, keeping her concentration on his attentive grin.

He let her slip past, turning to watch her face him as she cautiously stepped around, eyes on the patch at her chest, and her bosom as well.

She backed away to the hall she'd entered, the helpless feeling of being out-matched overwhelming her sensibilities. His grin turned to a smile, a livid flash in his eyes as she edged to the corridor. She was about to duck out of the room and shunpo to where she hoped the bulk of shinigami were when he spoke again.

"He didn't have to die, you know."

The words could have meant a dozen things, but Rangiku knew what he meant. Suddenly the safety she might have had at escape fell from her options, months of suppressed rage leaping into its place, and she launched.

"You bastard!" she bit out, teeth clenched so tight that the words were a mere grunt.

With a force she hadn't used in months, Rangiku's blade slashed at his chest, aiming for the scar Ichigo had made. Grimmjow's sword met hers, effortlessly halting the impact before throwing her back.

She nearly fell from the force, but she remained on her feet, glaring at the audacity of the smile he wore as he followed through with a swipe that jarred every bone in her arm. It was too much, she knew, but she blocked it and retaliated, wasting no strength to scream at him.

He met the clash and stepped to one side, catching the next volley of slashes she delivered, grinning at her effort. He returned a few, each met by her blade with resolve more than skill to keep the edge form her. They circled twice, away from the corridor, skirting the stairs. He never pushed the battle up the steps, for which she was grateful, whether by chance or design.

What seemed half an hour was only minutes, she knew, but the power behind his attack taxed her with every movement. And always with that smirk.

"That's it?" he said, throwing her back as Haineko met Pantera in a deadly lock a moment later. He kept the stalemate, leaning in across the blades to force her down to brace against him, enjoying the labored breathing that moved her shirt. "This is all you've got? Weak, woman."

She strained against the blade, knowing hurt was no match for brute strength in any battle. She shoved her weight into the impasse, feeling him give little way. "Growl, Hai —!"

Before she could finish the command his hand grabbed the blade mid-length, pulling it toward him a few inches. "You don't want to call out that cat, shinigami," he said, voice dropping to a deadly low.

He pushed her sword and her to the wall, letting his forearm hold the katana steel at her chest.

"There are three divisions here," she bit out, straining to speak against the force on her.

Grimmjow only leaned closer, eyes lowering to the rapid breathing beneath her breasts his weight made as her back pinned to the wall. He grinned, but it was a tempered expression, something less cutting in his stare. "You don't fight better wounded, shinigami. You let memories get in the way."

She shoved back at him, but he only let his full weight press on her. "Don't ever speak about him."

He looked to the blades between them and let his free hand run down the length of Haineko, watching her eyes follow the slit of blood that appeared on his palm. He also saw the fear that leaped into their blue depths. "He spoke about you."

She shook her head, feeling her strength failing.

"Yes, he did." He took his hand from the sword and picked the blue patch from her chest.

"Don't do that," she said before she thought the words through, the air around them seeming to change in density.

"You feel that? Me. Not some dim reiatsu you want to ignore. Me," he said, leaning closer as he held up the patch, eyes still on hers. "You ever get it out of your system? Ever grind a little at the injustice of the War?" he asked, letting his sword inch down hers a bit. "Ever take that cat out and beat someone for it?"

"You vulgar _Arrancar_," she said, wishing she could spit or think of a worse insult.

He chuckled, shaking his head, his hair barely touching the top of hers. "You should call out your zanpakutou on someone who can take it, shinigami." His gaze dropped to her chest, grinning at the movements her panting made as she tried to hold against his sword.

Her eyes fell to his hand holding the patch, seeing the few spots of blood on his fingers, knowing what it could mean, if Grimmjow was in the mood for a real fight.

For a moment he watched her forced exhale, letting her rapid breath on his face keep rhythm with the heartbeat he could see in her chest.

He stepped back, pulling his blade from hers as she sagged against the wall, grip tight but fatigued. He shook his head at her unsteady stance, her hand beginning to shake on the sword hilt.

He held up the patch, grinning. "Next time you want to vent, come cross swords with me." He laughed, turning his back on her. "You know where to find me. Matsumoto."

Rangiku swallowed down her fear, her legs weak, her arms aching. She watched him dissolve into the shadows, catching her breath. She swallowed, both in relief and some of her wounded loneliness of the last few months. After all, saké only went so far.

"Stupid leftover," she said aloud between gasps, watching for any sign of Grimmjow's return.

There was none, and after a moment she chanced to make her way to the corridor, cautious of any attack.

She saw no one as she returned to the rest of the shinigami divisions, who were in stages of packing their few necessities for the trip back to Soul Society.

"Hey, where have you been?" Izuru called as he caught up with her at the hall entrance. He frowned at her weariness, eyes dropping to her chest devoid of the blue patch.

Or that's what she figured he'd say he was looking at, she knew.

"We can take those off now?" He rubbed his chest where his own patch was located, giving her a more thorough study. "Are you okay, Rangiku?"

She nodded, strangely feeling no urgency to tell him about her recent meeting with the Espada. "It kept falling off," she said, fingering her lapel, wondering why the words failed her when she felt she should tell him the truth. "I'm so tired of being here, Izuru."

He sighed, nodding, his posture losing some of its stance. "This place sucks the life out of everyone, except Nemu. Maybe next time Captain Kurotsuchi can bring different divisions."

Rangiku nodded, eyes shifting to the corridor behind her. "Maybe."

"Matsumoto!" Hitsugaya's voice rang out from the midst of the packing.

She glanced that way, unable to find her captain among the taller black robes milling around the gear.

"Ready?" Izuru asked.

She nodded. "Ready."


End file.
